So this is neat. Potentially life changing for some type 2 diabetics, but that depends because some t2 diabetics are not failing to make enough insulin, they're just no longer sensitive to it at a level that makes it functional for them. I suppose it's possible that this therapy could cause them to grow enough islet β cells to overcome their lack of sensitivity, but (and I'm a type 1, not a type 2, so maybe my info is incorrect here) that lack of sensitivity can grow with further exposure to insulin making this a stop-gap at best for those cases absent other therapies.

...and with all of that said, being able to regrow islet β cells has never really been the problem for type 1 diabetes. You can regrow all the islet β cells you'd like and it's not going to cure the underlying immune disease that has caused your immune system to kill off all of your islet β cells to begin with. Unless you can figure out why t1 diabetes causes one's own immune system to go psycho killer on their islet β cells, you've done nothing to "cure" diabetes. Without being able to suppress that impulse for your immune system to murder your own cells, any ability to replace the islet β cells is going to be temporary at best, and probably a waste on the whole.

My brother in law is a "cured" type 1 diabetic, by virtue of his having had a kidney replacement and being on immune suppressing drugs for that. Since they were already replacing the kidney and he was going to have to take immune system suppression medications for that, they also just replaced his pancreas at the same time and the suppression of his immune system has allowed the new pancreas to thrive and continue to make insulin. Easy-peasy. The only trade-off is that he is super immunocompromised and can be killed by common colds, so not a great strategy in general.